The euthanasia argument is in the news again. Some doctors and general purpose campaigners want to be able to kill people off when they are dying, decrepit, expensive, unable to complete an Iron Man Triathalon or in a great deal of pain. Others worry about making killing legal. I’m one of the worriers. I can see all sorts of problems.

As I’ve become older I’ve realised that when things can go wrong they often do.

I worry more than I did when I was young because I have more experience of the frequency with which serious problems can occur, and the consequences which can result from unexpected misinterpretations and confusions.

The Government has already given doctors the legal right to kill people over the age of 70 (by starving them to death, or depriving them of fluids) if they are filling a hospital bed that the administrators want to use for a patient requiring cosmetic surgery or infertility treatment.

I can see the government taking advantage of a euthanasia law to get rid of all sorts of patients with chronic or potentially expensive illnesses; assisted dying will metamorphose into something quite different to the gentle and kindly easing the proponents envisage.

Is there anyone in the land who would trust a politician to decide when they should be ‘put to sleep’?

I fear that if a euthanasia law is introduced, it will mark the return of the death penalty. But this time we won’t be killing the probably guilty; we will be killing the definitely innocent.

One additional problem is that it is utterly impossible to predict when a dying patient will die. Anyone who says they can do so is a fraud, a crook, a cheat and a liar.

The world is full of people who are still breathing and living full lives despite having been diagnosed as being terminally ill.

I heard this week about a doctor in County Antrim, Northern Ireland who was wrongly diagnosed with terminal cancer and told to prepare for death. She was told that she had three months to live. Fortunately, being a doctor, the patient discharged herself, went to a London hospital and was diagnosed as having gallstones. Twenty five years ago I myself was diagnosed as having kidney cancer. I requested a second opinion. The diagnosis was changed.

It wouldn’t be difficult to fill a large book with such stories. When I was a GP I saw a number of patients who lived far longer than seemed possible – often because they had a very good reason not to die. One patient, a young prostitute with three small children, was dying of bowel cancer. She survived far beyond anyone’s expectations, and simply would not die until she was happy that a good home had been found for her children.

I remember the night I diagnosed her condition and sent her into hospital for the first time. I had no idea what to do with her three small children. I was on call for the night and living in a bachelor flat so I could hardly take them home with me. There were no neighbours, friends or relatives to care for them. I rang the emergency telephone number for the social services department, and the social worker on call told me that he couldn’t possibly help. When I asked why he could not come out, collect the children and take them to a children’s home for the night he told me that he couldn’t leave his telephone in case someone rang with an emergency. I ended up taking the children to a nearby nunnery where I was the nunnery’s medical officer.

The other patient was the wife of an alcoholic playwright and the mother of two teenage children. She had breast cancer but refused to die until her children had grown up. She had secondaries in just about every organ in her body but still she wouldn’t die. I remember sending a sample of her blood to the laboratory to be tested. They rang me up and asked me what I was playing at. They said that no one could be alive with the blood readings they’d taken. But she was alive. And she lived for several more years. I just stopped taking blood samples because there wasn’t any point.

Taken from Vernon Coleman’s diary 'Bugger Off and Leave Me Alone’, published as an eBook on Amazon